Protecting biodiversity is essential to our health and longevity on this planet. But can we quantify that value? Especially the economic value?

Late last year, researchers from the US and France attempted to put dollar amounts on the importance of biodiversity by correlating it to the prevalence of tropical disease in developing countries. According to their introduction in PLoS Biology:

Along with 93% of the global burden of vector-borne and parasitic diseases (VBPDs), the tropics host 41 of the 48 “least developed countries” and only two of 34 “advanced economies.”

They contend that economic growth falters when people get sick. (Seems reasonable.) And the spread of disease among humans, many scientists argue, can increase or decrease depending on factors in the natural environment, including biodiversity.

The more diverse an ecosystem, the greater the chance that a pathogen is diluted among numerous and potentially less-than-ideal host species and, therefore, the less abundant the disease. In 2002, researchers found this to be true with Lyme disease. NPR sums it up well:

If you have a rich community of tick hosts, like squirrels, mice and other small mammals, the disease is diluted among them. But if the habitat is degraded, and ticks carrying Lyme have only white-footed mice as hosts, the disease risk to humans can rise dramatically.

The Academy’s microbiologist, Shannon Bennett, weighed in on biodiversity’s impact on human diseases. In a recent email, she wrote:

I am sure biodiversity influences the transmission of infectious diseases one way or another.  Over 75% of new, emerging or re-emerging human diseases are caused by pathogens from animals, according to the World Health Organization. That means that the ecological communities we live in, and how pathogens cycle through the different players, are key to human health. Biodiversity is one way that we measure the complexity of these communities. In what way biodiversity is important, or how these communities specifically affect infectious diseases and risk, depends on the pathogen ecology and life history, and host species relationships.

Stanford researchers brought up this same point last month—“depends on the particulars,” as Bennett put it—in a study in Ecology Letters. A summary from the Stanford Report states:

The researchers found that the links between biodiversity and disease prevalence are variable and dependent on the disease system, local ecology and probably human social context.

The role of individual host species and their interactions with other hosts, vectors and pathogens are more influential in determining local disease risk, the analysis found.

That dovetails exactly with the research Bennett and Academy entomologist Durrell Kapan are conducting. They’re currently studying mosquito vector communities and the relationships between their biodiversity, the diversity of their microbes, and the presence of pathogens.

As for putting a price tag on biodiversity, Bennett encourages the PLoS study’s authors:

I find the authors’ argument intriguing and certainly a significant angle to consider in support of the health value of biodiversity, and one that is unique—no one has teased out the financial correlations between biodiversity and human societies. That it includes human health and infectious diseases is the angle I find particularly intriguing and worth following up on with empirical studies.

And on these studies of human disease and biodiversity in general? Bennett is excited about the possibilities of further research, including her own:

Increasingly we are recognizing and appreciating that humans are members of complex communities of other species, and that the make-up of these communities, whether they live inside of us or outside, can be very important to human health, as well as the health of all life. Human health and the health of life on this planet are coupled. We need to understand those coupling mechanisms better to ensure sustainability of that life, and the best way to understand those coupling mechanisms is with a multi-disciplinary approach, bringing together human health researchers with ecologists and evolutionary biologists, to name a few!

Some organizations have sprung up to do just that. Bennett points to two examples: the One Health Initiative and the EcoHealth Association. Whatever dollar value we assign to biodiversity and other ecosystem services, let’s wish these organizations luck in improving human health and well-being.

Image: CDC

Last month, a rare octopus species—the Larger Pacific Striped Octopus—moved into the Animal Attraction exhibit at the Academy. As the news spread, Academy Senior Biologist Richard Ross had already turned his attention to the challenging work behind-the-scenes by partnering with UC Berkeley professor Roy Caldwell on a multi-year, painstaking project to describe a species so obscure that it still lacks a scientific name. And even more challenging, Ross, whose expertise and enthusiasm is focused on cephalopods and corals, is hoping to breed this species from paralarvae (as octopus hatchlings are called) to a self-sustaining octopus.

“There are no guarantees of success,” says Ross. “Raising larval marine animals is hard. The entire aquatic community faces the same hurdle—how do you feed the new hatchings and keep them alive? It’s a tough nut to crack.”

“The first food is the stumbling block,” explains Charles Delbeek, Assistant Curator for the Steinhart Aquarium. “Their mouths are so small their first food item has to be correspondingly tiny.” When using appropriate-sized substitutes for plankton, “there’s no guarantee they’ll swim the right way and attract the hatchlings attention, striking and eating. Or let’s say they do eat—does the first food item have the proper nutritional profile? Are they eating only to slowly starve to death?”

New food sources such as rotifers, copepods, baby brine shrimp,and other tiny larvae are all helping the field advance. “A lot of the advances are being made by private people in their own homes,” Ross adds.

Maybe that’s why Ross is breeding octopuses in a 4x2x2 foot, 100-gallon tank in his Alameda home. “It helps to focus on the creatures full force—just them, getting them to breed, getting them to eat. That’s how I cracked the nut of breeding Dwarf Cuttlefish.”

Ross is referring to the 2009 breeding program when the Academy made headlines as the first public aquarium to close the life cycle for Dwarf Cuttlefish (Sepia bandensis) which Ross initially accomplished in his secret home lab in 2006. In addition, Academy biologists have bred seahorses, pipefish, and jellyfish. They have also purchased tank-bred species of saltwater coral reef fish, such as clownfish, blennies, and cardinal fish.

“Our great almost-success was the ghost pipefish,” he adds, referring to brood stock from the Philippines that mated successfully at the Aquarium. “That had never been done by a public aquarium before,” says Ross, “and we kept the larvae alive for 22 days.”

Most fresh water fish and amphibians do not pose the same challenge, he notes. Academy herpetologists, for example, work closely with the aquarium on thriving killifish, frog, bug, and tadpole-breeding programs.

The reality of the Larger Pacific Striped Octopus came to Ross’ attention 13 months ago, in February 2012. He and Roy Caldwell had been researching a cousin of the octopus species—the Lesser Pacific Striped Octopus (Octopus chierchiae)—obtaining live specimens from a collector in Central America.

“He got in touch with us last January to say he found a much larger octopus than the O. chierchiae. Did we want to see it?” Ross laughs, “Oh, yes! We nearly jumped up and down at the offer.”

The Larger Pacific Striped Octopus was originally discovered in 1991 by Panamanian biologist Aradio Rodaniche, who briefly described it and published a line drawing.

“It was exciting and intriguing,” Ross recalls. “He wrote about some unusual behaviors. For example, they lay multiple clutches of eggs. But no one saw another one for more than 20 years.”

Since Ross and Caldwell switched gears to focus their study on this species, they’ve observed a number of traits that make the Larger Pacific Striped Octopus unique as well as rare. “They’re gregarious,” he says, ticking off a list, which means they can live in social groups, unlike most octopus species which are cannibalistic. “They mate beak-to-beak. They’re cooler water animals, so they should live longer. And they have stripes and spots and change color bilaterally.” Ross shakes his head happily. “It’s nuts! He exclaims. “I’ve never seen anything like them.”

The two biologists and colleagues will take approximately two years to study and describe the species. But a more immediate challenge remains finding a way to feed the new hatchlings.

For the Academy, where conservation is a central part of its mission, breeding efforts such as Ross’ will only become increasingly important.

“It’s our strategic goal to be the place to see rare and unusual animals,” adds Delbeek, the Aquarium’s assistant curator. “That said, we all recognize that in 20 to 30 years, the likelihood of being able go into the wild and scoop up animals will be much lower. So we’ve got to do a better job of breeding in-house to reach our long term goal of being self-sustaining.”

Barbara Tannenbaum is a science writer working with the Academy’s Digital Engagement Studio. Her work has appeared in the New York Times, San Francisco Magazine and many other publications.

Image: Rich Ross

Invasive species often worry scientists—how will native species respond to competition in their ecosystem? The Academy’s Brian Simison shares this concern, but he looks a little deeper. He asks: how does invasive species’ DNA affect that of native species?

Studying slider turtles (Trachemys) is a good way to this address this question. Some species, like the abundant red-eared slider, are invasive all over the world. Others are threatened native species. The invasive and native species often mate with each other, creating offspring. This mixing of two species genomes through crossing, that is, hybridization, can have a profound effect on the evolution of these species and on ecosystem health.

Recently Brian and Academy Research Associate James Parham of CSU Fullerton published a paper on slider populations in the Caribbean. The native sliders there “are endangered, largely because of habitat destruction, and being harvested for food,” Brian explains.

In some places, natives are also threatened by invasive species like the Cuban slider on Jamaica or the red-eared slider in Puerto Rico. “It appears that people have been moving turtles around for hundreds of years, and for some islands there may have been different sources of the introductions,” Brian says.

The recent study reveals a lot of hybridization among the invasive and native species. “We used genetic data to show that there are multiple hybridization events, both recent and ancient, both from natural contact and because of human activities,” Brian describes. “This pattern also shows that the past and ongoing movement of turtles by humans is impacting their DNA.”

But Brian suspects that human impacts may not be the only reason for hybridization. “In addition to the genetic pollution caused by people moving turtles into the range of other turtles, different species also contact each other naturally. So hybridization may be an important part of the natural evolution of these turtles. We have to keep this in mind when reconstructing their evolutionary history. We also need to be very careful determining whether evolution is the result of unnatural (human) or natural processes.”

If hybridization is due to unnatural, human causes, conservation efforts are a top priority in protecting the native turtles from the invasive species. Brian and his colleagues are also confronting these hybridization and conservation issues in the US. “The turtle project is a long-term multi-component project that will last for decades. This publication about Caribbean turtles is a small piece of the entire slider puzzle, which we are unraveling piece by piece.”

And the project goes beyond turtles. “Another facet of the current study addresses how we study genomic data in species that are hybridizing. In other words, we demonstrate how the presence of hybridization confounds certain methods that people are using to reconstruct how different species are related.”

These turtles get to the root of Brian’s work. “Asking, testing and answering evolutionary questions is why I became a scientist,” he explains. “Turtles are one of the few vertebrates that hybridize across deep historical divisions, which provides my colleagues and me the opportunity to test some of the most fundamental questions about the processes of speciation, the engine generating biodiversity.”

Image: James Parham

When you and I look at spiders, we might see something creepy or cool (depending on your inclination), but when these scientists look at spiders, they see millions of years in the past.

Charles Griswold, Hannah Wood, Rosemary Gillespie and Nick Matzke painstakingly studied a superfamily of spiders called Palpimanoidea, aka assassin spiders.

The Academy and University of California researchers wanted to determine how these spiders are related and distributed and how that’s changed for the millions of years they have lived on Earth.

This superfamily has been assembled and separated many times over the past three decades.  The superfamily includes the trap jaw spiders (Mecysmaucheniidae), forest rubies (Stenochilidae), the mysterious Hutton’s spider (Huttoniidae), palp-footed spiders (Palpimanidae) and the pelican spiders (Archaeidae).

They’re called assassin spiders because all of the families except the trap jaw spiders hunt, kill and eat other spiders. Trap jaw spiders have an unusual feeding pattern, too. They have incredibly strong and fast jaws that lock open and then release quickly to trap prey.

While most of the living species within the assassin spiders live in the southern hemisphere, grouping these spiders is tricky because they have disjunct distributions, separated by barriers, namely large oceans.

Scientists love when things are tricky: it raises new questions to research. That couldn’t be more true for this group of folks. Charles has always been interested in biogeography and continental drift. Rosie Gillespie has always been interested in life on islands—what lives there, how did it get there and how did it diversify? Hannah’s fascinated by the pelican spiders and Nick is a paleontologist and computational biologist, attracted by the statistics of dating phylogenies.

It’s good that their interests are diverse, Charles says. “Science has become technologically and mathematically complex. It now requires a team of researchers.”

Hannah and Charles traveled throughout the southern hemisphere collecting and studying these spiders for many years. To answer the tricky questions this superfamily poses, they began with a thorough comparative morphology of all the spiders, living and extinct. Many of the fossils were specimens trapped in amber—which preserves the spiders “like new,” Charles says.

The scientists used whatever tools they could get their hands on—microscopy, current dissection technology, CT-scans, even the synchrotron at the Advanced Light Source at UC Berkeley.

The team gleaned data from DNA collected for every living spider. Then came the number crunching. Data were processed on the computer cluster here at the Academy and the San Diego Super Computer Center.

Charles explains that their findings confirm four different theories.

First, they confirm that these spiders all belong to Palpimanoidea.  “The phylogeny and classification encompasses the true scope of the superfamily,” Charles says.

Second, one of the fossil spiders they studied, an Archaeidae species, was discovered in the northern hemisphere. But all of the living relatives reside in the southern hemisphere. As David Byrne might ask, “How did I get here?” Charles and Hannah have an answer—continental drift. The lineage is so ancient, it’s consistent with the dates of continental drift.

Third and fourth, these spiders are found on the islands of Madagascar and New Zealand.  Geologists know that these two islands were originally pieces of their nearby continents that became separated. When they broke-off is clear, Charles says, but what is controversial is if some life forms have been around since the islands were connected to continent. .  Many animals and plants may have dispersed there.  The dates of these spiders originate prior to island separation, showing they have endured since the islands first broke away from the continents.

This superfamily of spiders, Charles says, is one of the “best examples of distribution that reflects continental drift. The distribution patterns, age of the fossils, and dates of phylogenic diversification are old enough. It’s one of the best documented cases of the results of continental drift.”

If you’ve seen our Earthquake exhibit, you know there are other examples of animal and plant evidence of continental drift. These spiders add nicely to it.

The study was published last month in Systematic Biology.

Charles will now take these methods to look at the biogeography of other groups of spiders. Hannah is looking more deeply into the trap jaw mechanism of those amazing spiders. Stay tuned for more spiderific stories!

Huttonia spider image: SE Thorpe/Wikipedia

In a rare piece of good news for coral reef resilience and sustainability, a team of scientists from Stanford University have confirmed the genetic basis for at least one species of coral, located in American Samoa, to adapt and thrive in an ecosystem characterized by extremely warm temperatures of water.

Corals that build coral reefs are living animals that secrete skeletons of calcium carbonate. One-celled algae called zooxanthellae live inside the coral polyps. Unlike a parasite, the symbiotic algae has a mutually beneficial relationship with the coral.

But excess heat has a deleterious effect on both algae and coral. When the ocean heats up, the algae stops making sugar and the coral flushes its partner out of the polyp. Lacking oxygen and other nutrients, the coral loses color. Such bleaching events, along with ocean acidification, pollution, coastal development, and overfishing, are factors that have led scientists to warn that 25% to 30% of the world’s coral reefs are already severely degraded. And that’s not taking into account the impact of rising sea surface temperatures in the next 50 years.

Thus, the environmental community expressed cautious optimism regarding Stephen Palumbi’s research results. The Stanford professor and director of the Hopkins Marine Station knew he’d found something unusual when he began studying a colony of Acropora hyacinthus corals off the Ofu Island in American Samoa in 2004—in a spot where the coral thrived in shallow pools of water less than five feet deep and temperatures soared over 94 degrees in the summer.

Palumbi and his team zeroed in on the comparative genomics of the coral located in the hot location, compared with snippets of the same species living in cooler waters sometimes only yards away.

The researchers found evidence of what Gary Williams, Academy curator in Invertebrate Zoology and Geology, calls preadaptation. In such cases, a species evolves to use a preexisting structure or trait inherited from an ancestor for a potentially unrelated function. In Ofu, the Stanford team discovered that the ongoing, seasonal exposure to warmer waters activated 60 genes that enable the symbiotic algae to combat heat-related stress. Palumbi’s team also pinpointed high levels of the protein ubiquitin that allow the algae to recycle molecules damaged by hot water.

“That’s interesting that they linked the cause of coral death by bleaching to a function of the algae’s immune system,” Williams said.

However, Williams cautions, “Bleaching does not automatically mean the coral has died.” It depends on how long or severe the bleaching event is. “There is always the potential that the algae can return and reinfect the host. Coral is more resilient than we realize.”

According to Williams, Academy scientists often see examples of this “on just about every expedition we take.” Referring to a 2006 dive in the Palmyra Atoll, 1200 miles south of Hawaii near the equator, Williams describes seeing patches of bleached coral, as well as some healthy and flourishing corals living very close to the surface in warm, brightly-lit water. “Coral bleaching is not usually permanent,” he explains. “The culprit of bleaching is probably an El Niño event that heats up parts of the western Pacific. But when the cooler waters—a.k.a. La Niña—comes back, the algae return and coral reef rebuilds and thrives.”

The larger implication “is that similar adaptations may also occur in other coral species,” says Williams. “In the future, we can hope that other types of coral will have the ability to respond to changing conditions in the same way.”

If not, Williams takes the long view. He pulls out a chart to show there are approximately 5,350 species of corals in the world. The greatest percentage—64%—is octocorals, which thrive in regions from shallow intertidal zones to depths as great as 6,000 meters or more.

“People say we’re losing coral at an unprecedented rate, but they’re only talking about the 750 hermatypic, reef-building species—14% of the total. When we speak of losing coral, we’re only speaking about this subgroup. Even in a worst-case scenario—mass extinctions of a majority of hermatypic corals—other successional, pioneer species will come in to fill the empty niche. Nature has a way of taking care of itself if you solve the underlying problem.”

Barbara Tannenbaum is a science writer working with the Academy’s Digital Engagement Studio. Her work has appeared in the New York Times, San Francisco Magazine and many other publications.

With headlines like, “Poorly-endowed barnacles overthrow 150-year-old belief,” this recent bit of research tugged at our heart-strings. So we consulted with our barnacle expert, Academy Research Fellow Bob Van Syoc, to understand the reproductive challenges facing this arthropod.

First thing you have to know about barnacles—they’re functionally sequential hermaphrodites. “That is, they are hermaphrodites that act as either male or female at any point in time, not both at the same time,” Van Syoc explains. “In all of these, ‘pseudo-copulation’ occurs by the transfer of sperm from the penis of the male inserted into the female or hermaphrodite mantle chamber where the eggs are fertilized and brooded until larvae hatch.”

Sounds like fun, right? And unlike the poor barnacle in the National Geographic blog title above, most barnacles are actually quite well-endowed. From ScienceNOW:

Even Charles Darwin marveled at the length of the barnacle’s penis. In some species, it’s up to eight times the body length.

Sadly, that’s not the case for the Pacific gooseneck barnacle, Pollicipes polymerus, the poorly-endowed barnacle of the title. And that’s not all. “As a stalked barnacle with a flexible peduncle it is relatively less evolved than the sessile, volcano-shaped shelled barnacles that are most common on our shores,” says Van Syoc.  “P. polymerus is a member of a relict genus that exists only in the eastern boundaries of the Pacific and Atlantic Oceans.”

Perhaps that’s why, size and all, these barnacles “spermcast,” according to a surprising study last month in the Proceedings of the Royal Society B. Spermcasting is just as it sounds—releasing sperm into the water column hoping for a bit of luck. For most barnacles, this doesn’t produce the best results.

Here’s how Van Syoc describes it: “Broadcast fertilization (or ‘spermcasting,’ as the authors have it) is wasteful of gametes and would not be expected in an efficient evolutionary sequence once internal fertilization has evolved.  However, it does increase the chance of sperm reaching a target egg and greatly increases the reach of individuals and their ability to fertilize more than a few individuals nearby.”

That P. polymerus spermcasts would have shocked even Darwin, who wrote quite a bit about barnacles and barnacle sex.

“The study challenges our traditional (i.e., since Darwin!) ideas of barnacle mating and fertilization,” Van Syoc says. But he likes the study and techniques the paper’s authors used. “It illustrates that field ecology observations (solitary individuals brooding embryos) coupled with modern DNA analysis techniques to help determine parentage can, and should, be used in concert. Too often, scientists either eschew new techniques as ‘trendy’ or traditional methods as ‘old fashioned.’ Here we have a great example of how they can work together to great effect.”

Image: Minette Layne/Wikipedia

That was the subject of the first event of Brilliant!Science, a week long biosciences festival co-hosted by the Academy and the Gladstone Institutes. “Infectious Cures: Hijacking Viruses To Overcome Disease” was an “intimate conversation” with Dr. Leor Weinberger of the Gladstone Institutes held Thursday at the Commonwealth Club.

Moderated by the Academy’s microbiologist, Shannon Bennett, Weinberger started the conversation by giving us the background of the bad guy virus—in this case, HIV.

First he gave us the numbers—HIV has killed 30 million people, 34 million are currently living with AIDS (the disease caused by HIV), 3.4 million of those are children and 16.6 million children have been orphaned due to the disease.

The antiviral drugs used to treat those infected with HIV are good, Weinberger stressed, but don’t reach everyone who needs them. Plus, the extreme regimen of taking the drugs makes it difficult for many who do have access. Weinberger also introduced the idea of the “superspreaders”—these are small groups of people that engage in high-risk behaviors and are more likely to transmit the virus. In the case of HIV in Africa, many of these superspreaders are sex workers and truck drivers.

With antivirals or a potential vaccine—even if these treatments were able to reach a large percentage of a population—superspreaders would greatly diminish the efficacy of these treatments. Think of superspreaders as the bad guy’s evil sidekick.

After Weinberger gave us an idea of how wicked a bad guy HIV truly is, he then explained how the virus commits its crimes inside our bodies.

HIV is perfectly suited to attack our white blood cells. Its external keys target white blood cells, hijacking them and turning the white blood cells into HIV-making factories.

Weinberger, like many researchers, wants to stop HIV in its tracks. In his lab, his team is genetically engineering HIV—keeping its outer structure virtually the same. He copies the genetic material within the virus and “erases” much of the code, making a smaller version that can replicate faster. He calls this smaller version TIPS, for Therapeutic Interfering Particles.

Because TIPS is similar to HIV, it can enter the white blood cell just as easily. But since TIPS is smaller and faster it can outcompete HIV, turning that white blood cell into a TIPS-making factory instead of an evil HIV factory.

Even better, TIPS is transmitted just like HIV, meaning those evil sidekicks—the superspreaders—actually begin transmitting TIPS, instead of HIV, to the very people that need access to something that stops HIV.

Even better still, TIPS is able to evolve as HIV evolves. One challenge of viruses is that they evolve quickly, becoming resistant to vaccines (think of our yearly flu shots). But TIPS is able to keep up with HIV.

This all sounds too good to be true, right? Weinberger and team have TIPS working well in petri dishes in their lab. But as with many new solutions, it needs more testing, more funding. From bench to market is at least five years in any situation, Weinberger said. So keep your fingers-crossed.

And if it works on bad guys like HIV, why not other viruses? Stay-tuned.